Langasque added a flawless 63 to his opening 68 at Crans-sur-Sierre to finish nine under par, a total later matched by England’s Richard Bland and Australia’s Richard Green.
The 21-year-old Langasque only turned professional after finishing 39th in the Masters in April, his trip to Augusta National secured by winning the Amateur Championship at Carnoustie last year.
But the world No 209 is already set to earn his full European Tour card via the Challenge Tour – he tops the rankings after six top-five finishes – and could secure a two-year exemption with victory in the Swiss Alps.
“This is really cool, but that’s what I want to do every week, so I will do my best now and we will see,” Langasque said after a round containing five birdies and an eagle.
“I’m quite sure I will be on the European Tour next year, so I play without pressure. If I play good that’s cool and if I play bad then it is no problem. I have nothing to lose. I have no pressure and maybe that’s why I can play good.”
In contrast to Langasque, Bland and Green have played more than 800 European Tour events between them, with Bland still seeking his first victory. The 43-year-old carded seven birdies and one bogey in his 64, while left-hander Green – whose last of three wins came in 2010 – held the outright lead after a hat-trick of birdies from the 13th before dropping his only shot of the day on the 17th.
Sweden’s Alex Noren, winner of the Scottish Open at Castle Stuart in July, matched Langasque’s 63 to share fourth place with Australian Scott Hend and Canada’s Richard Lee on eight under, with England’s Andrew Johnston among a five-strong group another stroke behind.
Defending champion Danny Willett had also been just two off the lead when he recovered from a bogey on the fourth with birdies on the sixth, seventh and ninth, but bogeyed the next two holes and then ran up a quadruple-bogey on the 12th after twice finding the water short of the green.
Willett bounced back with birdies on the 14th and 18th to finish three under par and saw playing partner and Ryder Cup team-mate Matt Fitzpatrick produce an even better finish to make the cut.
Fitzpatrick was seven over par for his first 14 holes on Thursday and eventually signed for a 75, but went ten shots better on yesterday and survived on the mark of level par thanks to four birdies in the last five holes. The final member of the Ryder Cup threesome, Andy Sullivan, almost pulled off the same feat after an opening 74, only to see his birdie chip on the 18th catch the edge of the hole and stay out. Sullivan’s 67 meant he missed the cut by a shot.
David Drysdale and Paul Lawrie are the leading Scots, sitting tied for 39th on two-under, one ahead of Richie Ramsay and two in front of Stephen Gallacher.
Elsewhere, Russell Knox and Martin Laird both made slow starts in the Deutsche Bank Championship, the second FedEx Cup Play-Off event, as they signed for 73 and 75 respectively to sit over par in Boston. England’s Paul Casey and Argentina’s Fabian Gomez had set the clubhouse target there on 66.